How Much Electricity Does a Heat Pump Use Monthly

Reviewed by a Certified Pool Technician (CPT)

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The Short Answer

Most pool heat pumps use between 4 and 7 kWh of electricity per hour, depending on size and efficiency. Monthly operating costs typically range from $50 to $300, depending on your electricity rate, climate, pool size, target water temperature, and daily runtime. At the U.S. average electricity rate of $0.16/kWh (2024), a heat pump running 6 hours daily costs approximately $58–$200/month for pools ranging from 10,000 to 35,000 gallons.

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Pool heat pump electricity costs confuse pool owners because the relationship between wattage, kWh, and monthly bills isn't always intuitive. This guide breaks down the real numbers what your specific pump size uses per hour, what that translates to per month, and how it compares to gas heating with enough practical detail to help you optimize your operating schedule and reduce costs.

 

How Much Does a Pool Heat Pump Cost Per Month to Run?

Pool Heat Pump Monthly Cost Calculator

Based on the U.S. average residential electricity rate of $0.16/kWh (EIA, 2024). Assumes maintaining temperature (not initial heating from cold).

Wattage ranges reflect operation at typical conditions. Actual consumption varies with ambient temperature, water temperature, and COP at current operating conditions.

Monthly Cost by Pool Size

Adjusting for Your Local Electricity Rate

Electricity rates vary significantly by region. Multiply the kWh consumption by your local rate to get your actual monthly cost:

 

Understanding COP: Why Heat Pumps Use Less Energy Than Gas

COP (Coefficient of Performance) is the ratio of heat energy delivered to electrical energy consumed. It's the key metric that makes heat pumps dramatically more economical than gas heaters.

How COP works:

• A heat pump with COP 6.4 delivers 6.4 units of heat for every 1 unit of electricity consumed

• This compares to a gas heater that delivers roughly 0.8 units of heat for every 1 unit of fuel energy consumed

• The heat pump is effectively 8× more efficient than gas at converting purchased energy into pool heat

Why COP is so high: A heat pump doesn't generate heat, it moves heat from the ambient air into the pool water. It's acting as a heat concentrator, not a heat generator. The electricity powers the compressor and fan; the actual heat energy comes from the air.

COP by temperature:

As temperature drops, COP drops, this is why cold-weather heat pump operation becomes less cost-effective. At 55°F ambient, a heat pump still outperforms gas but by a smaller margin.

Heat Pump vs. Gas Pool Heater: Monthly Energy Costs

This comparison is where the heat pump's operating cost advantage is most visible.

Monthly Cost Comparison: 20,000-Gallon Pool

Maintaining 82°F pool temperature, temperate climate.

Annual savings vs. gas (same 20,000-gallon pool, 6-month season):

• Heat pump vs. natural gas: $840–$1,410/year in savings

• Heat pump vs. propane: $1,560–$2,460/year in savings

Payback calculation: A heat pump priced $1,200 more than the equivalent gas heater, saving $1,000/year in operating costs, pays back in approximately 14–15 months.

 

What Factors Affect Heat Pump Electricity Usage?

Ambient air temperature. The most significant variable. At 80°F ambient, COP is 6.4 and electricity consumption is low. At 60°F ambient, COP drops to ~3.5, the heat pump needs to run longer (and consume more electricity) to deliver the same heat output. A month where ambient temperatures average 60°F costs 50–80% more to heat than a month where they average 80°F.

Pool water temperature target. Every degree of pool temperature above ambient air temperature costs more to maintain. The difference between maintaining 78°F vs. 84°F can be 15–25% more electricity consumption.

Pool surface area and cover use. A pool without a cover loses 4–7°F of heat overnight through evaporation and radiation. The heat pump must replace this loss daily. A solar cover reduces this loss by 50–70%, dramatically reducing daily runtime and monthly costs. See the pool cover section below.

Climate and humidity. High-humidity climates (Southeast, Gulf Coast) allow heat pumps to extract more heat from the air, COP is higher in humid conditions than dry ones at the same temperature. Desert climates with low humidity see slightly lower COP values.

Initial heating vs. maintenance. The monthly cost figures above assume maintaining temperature, the heat pump running 6–8 hours daily to replace daily heat loss. Initial heating from a cold pool (raising temperature 15–20°F from startup) consumes substantially more electricity over a 24–72-hour period. This first-heat event is a one-time cost each season.

Pool Heat Pump Electricity Cost Calculator

Your monthly cost formula:

Monthly cost = Wattage (kW) × Daily runtime (hours) × 30 days × Your electricity rate ($/kWh)

Example: 110,000 BTU heat pump (2,700W = 2.7 kW), 6 hours/day, $0.16/kWh: 2.7 kW × 6 hours × 30 days × $0.16 = $77.76/month

Finding your pump's wattage:

1. Check the unit's specification label (usually on the side or back panel) — look for "Watts" or "Amps × Volts = Watts"

2. Alternatively, use a smart plug with energy monitoring for real-world consumption data

3. Or use the BTU-to-wattage relationship: BTU/hr ÷ (3.413 × COP) = Watts. For a 110,000 BTU pump with COP 6.4: 110,000 ÷ (3.413 × 6.4) = ~5,030 watts... wait, that's the heat output. For electrical input: kWh per hour = BTU output ÷ (3,413 × COP) = 110,000 ÷ (3,413 × 6.4) = 5.04 kWh/hr... this simplifies to: Electrical input (kW) = BTU output ÷ (3,413 × COP)

Simplified for BLACK+DECKER/ComforTemp models (COP 6.4):

• 53,000 BTU: ~2.43 kW input

• 80,000 BTU: ~3.66 kW input

• 110,000 BTU: ~5.04 kW input

• 137,000 BTU: ~6.28 kW input

Note: Wattage listed on the unit specification label reflects the electrical input. The BTU rating reflects heat output. These differ by the COP multiplier.

How to Reduce Pool Heating Costs

Use a solar cover consistently. A solar cover reducing overnight heat loss by 50–70% is the single highest-return investment for reducing heat pump operating costs. A pool that loses 5°F overnight without a cover loses only 1.5–2°F with one — dramatically reducing the daily runtime needed to restore temperature. For most pool owners, consistent solar cover use saves 30–50% on monthly heating costs.

Set temperature lower when not in use. Every degree of maintained water temperature costs money. Dropping the setpoint 4–6°F during extended periods of non-use (weekdays when the pool isn't being used) saves meaningful electricity. Most modern heat pump controllers have scheduling functions; use them.

Run during peak ambient temperature hours. Heat pump efficiency peaks when ambient air temperature peaks. Running the heat pump 10 AM to 6 PM (when air is warmest) extracts heat more efficiently than running midnight to 8 AM.

Maintain the filter. A dirty filter reduces water flow, which reduces heat exchanger efficiency and extends the runtime needed to heat the pool to target temperature. A clean filter is a prerequisite for efficient heat pump operation.

Protect the equipment from wind. Wind cooling the evaporator coils reduces COP by creating a colder effective air temperature at the coil surface. If your equipment pad is in a very exposed, windy location, a windbreak (fence, hedge, or screen) positioned upwind of the heat pump can improve efficiency during windy conditions. See our pool equipment freeze and weather protection guide.

Upgrade your pool pump. Your pool pump must be running for the heat pump to operate. If you're running a single-speed pool pump, its electricity consumption adds to your total pool heating system cost. A variable-speed pool pump saves $200–$500/year that should be counted in the heat pump system's energy cost analysis. See our guide on replacing your pool pump with a variable-speed model and our most energy-efficient pool heating guide.

Best Temperature Settings to Save Energy

Target the lowest comfortable temperature. Each degree of pool temperature above ambient air temperature costs proportionally more to maintain. The difference between 78°F and 84°F can represent 15–25% more monthly electricity consumption for the same pool.

Typical comfortable pool temperature ranges:

• Recreational swimming: 78–82°F

• Lap swimming / exercise: 76–80°F

• Young children: 82–86°F

• Hot tub / spa: 100–104°F

Use setback scheduling: Program the heat pump thermostat to drop 4–6°F during periods of non-use:

• Raise to target temperature 2–3 hours before use (heat pumps heat slowly — plan ahead)

• Drop to setback temperature after use or during extended absence

• Don't drop more than 8–10°F recovering more than 10°F of temperature takes disproportionally long and may consume more energy than modest setback saves

Winter setback in mild climates: In climates where the pool runs year-round, reducing the target temperature from 82°F to 76°F during the winter months (when ambient temps are lower and heating efficiency is reduced) saves 20–35% on winter heating costs while keeping the pool usable.

Does a Pool Cover Reduce Heat Pump Electricity Usage?

Yes, significantly. A pool cover is the most cost-effective tool for reducing heat pump operating costs.

The mechanism: Approximately 70% of pool heat loss occurs at the water surface through evaporation and convective/radiative cooling. A solar cover blocks both evaporation and radiant cooling from the surface, the two largest heat loss pathways.

Quantified impact:

• Without cover: Typical overnight heat loss of 4–7°F in temperate conditions

• With solar cover: Overnight heat loss of 1–2°F

Monthly electricity savings from consistent cover use:

Estimates based on consistent nightly cover use and temperate climate conditions.

Return on cover investment: A quality solar cover costs $50–$200. At $35–$55/month in electricity savings, the cover pays for itself within the first 1–3 months of use.

 

Frequently Asked Questions

How much electricity does a pool heat pump use per hour?

Most residential pool heat pumps use 1.5–4 kWh per hour depending on BTU output and COP. A 110,000 BTU heat pump with COP 6.4 uses approximately 5 kWh per hour of operation, delivering 6.4 units of heat for every 1 unit of electricity consumed.

How much does it cost to run a pool heat pump per month?

At the U.S. average of $0.16/kWh, monthly costs typically range from $43–$150 depending on pool size, runtime, and climate. Small pools (10,000 gallons) cost approximately $43–$69/month; large pools (25,000+ gallons) run $110–$147/month. Adjust for your local electricity rate.

Is a pool heat pump cheaper to run than a gas heater?

Yes, typically 60–75% cheaper for equivalent heating output. A gas heater for a 20,000-gallon pool might cost $225–$350/month in natural gas; a comparable heat pump costs $86–$115/month in electricity.

What is COP and why does it matter for electricity usage?

COP (Coefficient of Performance) measures heat energy output per unit of electricity consumed. A COP of 6.4 means the heat pump delivers 6.4 units of heat for 1 unit of electricity, making it 6–8× more energy-efficient than a gas heater. Higher COP = lower electricity consumption per degree of pool heating.

Does a solar cover really reduce heat pump electricity usage?

Yes, significantly. A solar cover reduces overnight heat loss by 50–70%, which means the heat pump needs to run fewer hours daily to maintain the target temperature. Monthly savings of 30–50% are typical for consistent cover users.

How long does a pool heat pump run each day?

Typically 4–8 hours per day to maintain temperature after initial heating. More in cooler weather (lower COP, more heat loss); less in warm weather. Initial heating from a cold pool at the start of the season may require 24–72 hours of continuous operation.

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This article was reviewed by a Certified Pool Technician (CPT). Electricity cost estimates use the U.S. EIA average residential electricity rate of $0.16/kWh as a baseline; verify your local rate for accurate personal projections. COP values reference AHRI standard test conditions (80°F ambient). Gas cost comparisons use $1.50/therm natural gas and $3.50/gallon propane as benchmark rates.